# (C) 2019-2020 lifegpc
# This file is part of bili.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
table='fZodR9XQDSUm21yCkr6zBqiveYah8bt4xsWpHnJE7jL5VG3guMTKNPAwcF'
tr={}
for i in range(58):
    tr[table[i]]=i
s=[11,10,3,8,4,6]
xor=177451812
add=8728348608
def debv(x):
    if len(x)==11 :
        x="BV1"+x[2:]
    r=0
    for i in range(6):
        r+=tr[x[s[i]]]*58**i
    return (r-add)^xor
def enbv(x):
    x=(x^xor)+add
    r=list('BV1  4 1 7  ')
    for i in range(6):
        r[s[i]]=table[x//58**i%58]
    return ''.join(r)
